When using full LTO it is possible that template function definition DIE
is bound to one compilation unit and it's declaration to another. We should
add function declaration attributes on behalf of its owner CU otherwise
we may end up with malformed file identifier in function declaration
DW_AT_decl_file attribute.
Differential revision: https://reviews.llvm.org/D58538
llvm-svn: 354978
Summary:
A store to an object whose lifetime is about to end can be removed.
See PR40550 for motivation.
Reviewers: niravd
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D57541
llvm-svn: 354244
In this patch SelectionDAG tries to salvage any dbg.values that are going to be
dropped, in case they can be recovered from Values in the current BB. It also
strengthens SelectionDAGs handling of dangling debug data, so that dbg.values
are *always* emitted (as Undef or otherwise) instead of dangling forever.
The motivation behind this patch exists in the new test case: a memory address
(here a bitcast and GEP) exist in one basic block, and a dbg.value referring to
the address is left in the 'next' block. The base pointer is live across all
basic blocks. In current llvm trunk the dbg.value cannot be encoded, and it
isn't even emitted as an Undef DBG_VALUE.
The change is simply: if we're definitely going to drop a dbg.value, repeatedly
apply salvageDebugInfo to its operand until either we find something that can
be encoded, or we can't salvage any further in which case we produce an Undef
DBG_VALUE. To know when we're "definitely going to drop a dbg.value",
SelectionDAG signals SelectionDAGBuilder when all IR instructions have been
encoded to force salvaging. This ensures that any dbg.value that's dangling
after DAG creation will have a corresponding DBG_VALUE encoded.
Differential Revision: https://reviews.llvm.org/D57694
llvm-svn: 353954
SelectionDAGBuilder has special handling for dbg.value intrinsics that are
understood to define the location of function parameters on entry to the
function. To enable this, we avoid recording a dbg.value as a virtual register
reference if it might be such a parameter, so that it later hits
EmitFuncArgumentDbgValue.
This patch reduces the set of circumstances where we avoid recording a
dbg.value as a virtual register reference, to allow more "normal" variables
to be recorded that way. We now only bypass for potential parameters if:
* The dbg.value operand is an Argument,
* The Variable is a parameter, and
* The Variable is not inlined.
meaning it's very likely that the dbg.value is a function-entry parameter
location.
Differential Revision: https://reviews.llvm.org/D57584
llvm-svn: 353948
Summary:
This is a follow-up to D57510. This patch stops DebugHandlerBase from
changing the starting label for the first non-overlapping,
register-described parameter DBG_VALUEs to the beginning of the
function. That code did not consider what defined the registers, which
could result in the ranges for the debug values starting before their
defining instructions. We currently do not emit debug values for
constant values directly at the start of the function, so this code is
still useful for such values, but my intention is to remove the code
from DebugHandlerBase completely when we get there. One reason for
removing it is that the code violates the history map's ranges, which I
think can make it quite confusing when troubleshooting.
In D57510, PrologEpilogInserter was amended so that parameter DBG_VALUEs
now are kept at the start of the entry block, even after emission of
prologue code. That was done to reduce the degradation of debug
completeness from this patch. PR40638 is another example, where the
lexical-scope trimming that LDV does, in combination with scheduling,
results in instructions after the prologue being left without locations.
There might be other cases where the DBG_VALUEs are pushed further down,
for which the DebugHandlerBase code may be helpful, but as it now quite
often result in incorrect locations, even after the prologue, it seems
better to remove that code, and try to work our way up with accurate
locations.
In the long run we should maybe not aim to provide accurate locations
inside the prologue. Some single location descriptions, at least those
referring to stack values, generate inaccurate values inside the
epilogue, so we maybe should not aim to achieve accuracy for location
lists. However, it seems that we now emit line number programs that can
result in GDB and LLDB stopping inside the prologue when doing line
number stepping into functions. See PR40188 for more information.
A summary of some of the changed test cases is available in PR40188#c2.
Reviewers: aprantl, dblaikie, rnk, jmorse
Reviewed By: aprantl
Subscribers: jdoerfert, jholewinski, jvesely, javed.absar, llvm-commits
Tags: #debug-info, #llvm
Differential Revision: https://reviews.llvm.org/D57511
llvm-svn: 353928
Salvaging a redundant load instruction into a debug expression hides a
memory read from optimisation passes. Passes that alter memory behaviour
(such as LICM promoting memory to a register) aren't aware of these debug
memory reads and leave them unaltered, making the debug variable location
point somewhere unsafe.
Teaching passes to know about these debug memory reads would be challenging
and probably incomplete. Finding dbg.value instructions that need to be fixed
would likely be computationally expensive too, as more analysis would be
required. It's better to not generate debug-memory-reads instead, alas.
Changed tests:
* DeadStoreElim: test for salvaging of intermediate operations contributing
to the dead store, instead of salvaging of the redundant load,
* GVN: remove debuginfo behaviour checks completely, this behaviour is still
covered by other tests,
* InstCombine: don't test for salvaged loads, we're removing that behaviour.
Differential Revision: https://reviews.llvm.org/D57962
llvm-svn: 353824
Summary:
This is a preparatory change for removing the code from
DebugHandlerBase::beginFunction() which changes the starting label for
the first non-overlapping DBG_VALUEs of parameters to the beginning of
the function. It does that to be able to show parameters when entering a
function. However, that code does not consider what defines the values,
which can result in the ranges for the debug values starting before
their defining instructions. That code is removed in a follow-up patch.
When prologue code is inserted, it leads to DBG_VALUEs that start
directly in the entry block being moved down after the prologue
instructions. This patch fixes that by stashing away DBG_VALUEs for
parameters before emitting the prologue, and then reinserts them at the
start of the block. This assumes that there is no target that somehow
clobbers parameter registers in the frame setup; there is no such case
in the lit tests at least.
See PR40188 for more information.
Reviewers: aprantl, dblaikie, rnk, jmorse
Reviewed By: aprantl
Subscribers: bjope, llvm-commits
Tags: #debug-info
Differential Revision: https://reviews.llvm.org/D57510
llvm-svn: 353823
This configuration (due to r349207) was intended not to emit any DWO CU,
but a degenerate CU was still being emitted - containing a header and a
DW_TAG_compile_unit with no attributes.
Under that situation, emit nothing to the .dwo file. (since this is a
dynamic property of the input the .dwo file is still emitted, just with
nothing in it (so a valid, but empty, ELF file) - if some other CU
didn't satisfy this criteria, its DWO CU would still go there, etc)
llvm-svn: 353771
Summary:
This patch fixes PR40587.
When a dbg.value instrinsic is emitted to the DAG
by using EmitFuncArgumentDbgValue the resulting
DBG_VALUE is hoisted to the beginning of the entry
block. I think the idea is to be able to locate
a formal argument already from the start of the
function.
However, EmitFuncArgumentDbgValue only checked that
the value that was used to describe a variable was
originating from a function parameter, not that the
variable itself actually was an argument to the
function. So when for example assigning a local
variable "local" the value from an argument "a",
the assocated DBG_VALUE instruction would be hoisted
to the beginning of the function, even if the scope
for "local" started somewhere else (or if "local"
was mapped to other values earlier in the function).
This patch adds some logic to EmitFuncArgumentDbgValue
to check that the variable being described actually
is an argument to the function. And that the dbg.value
being lowered already is in the entry block. Otherwise
we bail out, and the dbg.value will be handled as an
ordinary dbg.value (not as a "FuncArgumentDbgValue").
A tricky situation is when both the variable and
the value is related to function arguments, but not
neccessarily the same argument. We make sure that we
do not describe the same argument more than once as
a "FuncArgumentDbgValue". This solution works as long
as opt has injected a "first" dbg.value that corresponds
to the formal argument at the function entry.
Reviewers: jmorse, aprantl
Subscribers: jyknight, hiraditya, fedor.sergeev, dstenb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57702
llvm-svn: 353735
Summary:
rL189250 added a realpath call, and rL352916 because realpath breaks assumptions with some build systems. However, the /usr/lib/debug case has been clarified, falling back to /usr/lib/debug is currently broken if the obj passed in is a relative path. Adding a call to use absolute paths when falling back to /usr/lib/debug fixes that while still not making any realpath assumptions.
This also adds a --fallback-debug-path command line flag for testing (since we probably can't write to /usr/lib/debug from buildbot environments), but was also verified manually:
```
$ rm -f path/to/dwarfdump-test.elf-x86-64
$ strace llvm-symbolizer --obj=relative/path/to/dwarfdump-test.elf-x86-64.debuglink 0x40113f |& grep dwarfdump
```
Lookups went to relative/path/to/dwarfdump-test.elf-x86-64, relative/path/to/.debug/dwarfdump-test.elf-x86-64, and then finally /usr/lib/debug/absolute/path/to/dwarfdump-test.elf-x86-64.
Reviewers: dblaikie, samsonov
Reviewed By: dblaikie
Subscribers: krytarowski, aprantl, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57916
llvm-svn: 353730
When a landing pad is calculated in a program that is compiled for micromips
with -fPIC flag, it will point to an even address.
Such an error will cause a segmentation fault, as the instructions in
micromips are aligned on odd addresses. This patch sets the last bit of the
offset where a landing pad is, to 1, which will effectively be an odd
address and point to the instruction exactly.
r344591 fixed this issue for -static compilation.
Patch by Aleksandar Beserminji.
Differential Revision: https://reviews.llvm.org/D57677
llvm-svn: 353480
This patch adds half a dozen new tests that test various edge cases in
the behaviour of the symbolizer and DWARF data parsing. All of them test
the current behaviour.
Reviewed by: JDevlieghere, aprantl
Differential Revision: https://reviews.llvm.org/D57741
llvm-svn: 353286
Summary:
According to
https://docs.nvidia.com/cuda/archive/10.0/ptx-writers-guide-to-interoperability/index.html#cuda-specific-dwarf,
the compiler should emit the DW_AT_address_class attribute for all
variable and parameter. It means, that DW_AT_address_class attribute
should be used in the non-standard way to support compatibility with the
cuda-gdb debugger.
Clang is able to generate the information about the variable address
class. This information is emitted as the expression sequence
`DW_OP_constu <DWARF Address Space> DW_OP_swap DW_OP_xderef`. The patch
tries to find all such expressions and transform them into
`DW_AT_address_class <DWARF Address Space>` if target is NVPTX and the debugger is gdb.
If the expression is not found, then default values are used. For the
local variables <DWARF Address Space> is set to ADDR_local_space(6), for
the globals <DWARF Address Space> is set to ADDR_global_space(5). The
values are taken from the table in the same section 5.2. CUDA-Specific
DWARF Definitions.
Reviewers: echristo, probinson
Subscribers: jholewinski, aprantl, llvm-commits
Differential Revision: https://reviews.llvm.org/D57157
llvm-svn: 353203
The LiveDebugValues pass recognizes spills but not restores, which can
cause large gaps in location information for some variables, depending
on control flow. This patch make LiveDebugValues recognize restores and
generate appropriate DBG_VALUE instructions.
This patch was posted previously with r352642 and reverted in r352666 due
to buildbot errors. A missing return statement was the cause for the
failures.
Reviewers: aprantl, NicolaPrica
Differential Revision: https://reviews.llvm.org/D57271
llvm-svn: 353089
Summary:
Using realpath makes assumptions about build systems that do not always hold true. The debug binary referred to from the .gnu_debuglink should exist in the same directory (or in a .debug directory, etc.), but the files may only exist as symlinks to a differently named files elsewhere, and using realpath causes that lookup to fail.
This was added in r189250, and this is basically a revert + regression test case.
Reviewers: dblaikie, samsonov, jhenderson
Reviewed By: dblaikie
Subscribers: llvm-commits, hiraditya
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57609
llvm-svn: 352916
Prior to this change, there are a few tests called llvm-symbolizer* in
the DebugInfo test area. These really were testing either the DebugInfo
or Symbolizer library, rather than the llvm-symbolizer tool itself, so
this patch renames them to be clearer that they aren't explicitly tests
for llvm-symbolizer (such tests belong in test/tools/llvm-symbolizer).
This patch also reinstates the copying of a DWO file, removed previously
in r352752. The test needs this so that it could possibly fail.
Finally, some of the tests have been simplified slightly by removing
unnecessary switches and/or unused check-prefixes.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D57518
llvm-svn: 352847
This is the fourth (and final for now) of a series of patches
simplifying llvm-symbolizer tests. See r352752, r352753 and 352754 for
the previous ones. This patch splits out several more distinct test
cases from llvm-symbolizer.test into separate tests, and simplifies them
in various ways including:
1) Building a test case for spaces in path from source, rather than
using a pre-canned binary. This allows deleting of said binary and the
source it was built from.
2) Switching to specifying addresses and objects directly on the
command-line rather than via stdin.
This also adds an explict test for the ability to specify a file and
address as a line in stdin, since the majority of the tests have been
migrated away from this approach, leaving this largely untested.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D57446
llvm-svn: 352756
This is the third of a series of patches simplifying llvm-symbolizer
tests. See r352752 and r352753 for the previous two. This patch splits
out a number of distinct test cases from llvm-symbolizer.test into
separate tests, and simplifies them in various ways including:
1) using --obj/positional arguments for the input file and addresses
instead of stdin,
2) using runtime-generated inputs rather than a pre-canned binary, and
3) testing more specifically (i.e. checking only what is interesting to
the behaviour changed in the original commit for that test case).
This patch also removes the test case for using --obj. The
tools/llvm-symbolizer/basic.s test already tests this case. Finally,
this patch adds a simple test case to the demangle switch test case to
show that demangling happens by default.
See https://bugs.llvm.org/show_bug.cgi?id=40070#c1 for the motivation.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D57446
llvm-svn: 352754
This is the second of a series of patches simplifying llvm-symbolizer
tests. See r352752 for the first. This one splits out 5 distinct test
cases from llvm-symbolizer.test into separate tests, and simplifies them
slightly by using --obj/positional arguments for the input file and
addresses instead of stdin.
See https://bugs.llvm.org/show_bug.cgi?id=40070#c1 for the motivation.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D57443
llvm-svn: 352753
This change migrates most llvm-symbolizer tests away from reading input
via stdin and instead using --obj + positional arguments for the file
and addresses respectively, which makes the tests easier to read.
One exception is the test test/tools/llvm-symbolizer/pdb/pdb.test, which
was doing some manipulation on the input addresses. This patch
simplifies this somewhat, but it still reads from stdin.
More changes to follow to simplify/break-up other tests.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D57441
llvm-svn: 352752
The LiveDebugValues pass recognizes spills but not restores, which can
cause large gaps in location information for some variables, depending
on control flow. This patch make LiveDebugValues recognize restores and
generate appropriate DBG_VALUE instructions.
Reviewers: aprantl, NicolaPrica
Differential Revision: https://reviews.llvm.org/D57271
llvm-svn: 352642
This test started XPASSing with r352467, and the change in behaviour
performed by that patch does appear to fix the cause of the original XFAIL
(missing FrameIndex DBG_VALUE), which I've replicated locally with
-mtriple=powerpc64--.
I'll write this up in PR21881 which documents the XFAIL, and seek
confirmation I haven't overlooked something here.
llvm-svn: 352471
A FrameIndex should be valid throughout a block regardless of what instructions
get selected in that block -- therefore we shouldn't harness dbg.values that
refer to FrameIndexes to an SDNode. There are numerous codegen reasons why
an SDNode never appears or doesn't become a location that a DBG_VALUE can
refer to. None of them actually affect the variable location.
Therefore, before any other tests to encode dbg_values in a SelectionDAG,
identify FrameIndex operands and encode them unattached to any SDNode.
Differential Revision: https://reviews.llvm.org/D57328
llvm-svn: 352467
This patch improves the placement of DBG_VALUEs when by SelectionDAG, which
as documented in PR40427 can go very wrong. At the core of this is
ProcessSourceNode, which assumes the last instruction in a BB is the start
of the last processed IR instruction, which isn't always true.
Instead, use a helper function to call InstrEmitter::EmitNode, that records
before-and-after iterators and determines the first of any new instruction
created during emission. This is passed to ProcessSourceNode, which can
then make more elightened decisions about ordering for DBG_VALUE placement.
Differential revision: https://reviews.llvm.org/D57163
llvm-svn: 352350
If bottom of block BB has only one successor OldTop, in most cases it is profitable to move it before OldTop, except the following case:
-->OldTop<-
| . |
| . |
| . |
---Pred |
| |
BB-----
Move BB before OldTop can't reduce the number of taken branches, this patch detects this case and prevent the moving.
Differential Revision: https://reviews.llvm.org/D57067
llvm-svn: 352236
This reapplies commit r351987 with a failed test fix. Now the test
accepts both DW_OP_GNU_push_tls_address and DW_OP_form_tls_address
opcode.
Original commit message:
```
This is a fix for a regression introduced by the rL348194 commit. In
that change new type (MEK_DTPREL) of MipsMCExpr expression was added,
but in some places of the code this type of expression considered as
unexpected.
This change fixes the bug. The MEK_DTPREL type of expression is used for
marking TLS DIEExpr only and contains a regular sub-expression. Where we
need to handle the expression, we retrieve the sub-expression and
handle it in a common way.
```
llvm-svn: 352034
Pulling out the split-dwarf tests by way of example of how I think
llvm-symbolizer should be tested going forward. Open to
debate/discussion, though.
llvm-svn: 352004
This is a fix for a regression introduced by the rL348194 commit. In
that change new type (MEK_DTPREL) of MipsMCExpr expression was added,
but in some places of the code this type of expression considered as
unexpected.
This change fixes the bug. The MEK_DTPREL type of expression is used for
marking TLS DIEExpr only and contains a regular sub-expression. Where we
need to handle the expression, we retrieve the sub-expression and
handle it in a common way.
llvm-svn: 351987
Enable full support for the debug info. Recommit to fix the emission of
the not required closing brace.
Differential revision: https://reviews.llvm.org/D46189
llvm-svn: 351972
This fixes https://bugs.llvm.org/show_bug.cgi?id=40072.
GNU addr2line's --functions switch is off by default, has a short alias
of -f, and does not take an argument. This patch changes llvm-symbolizer
to allow the second and third point (changing the default behaviour may
have negative impacts on users). If the option is missing a value, it
now treats it as "linkage".
This change does cause one previously valid command-line to behave
differently. Before --functions <value> was accepted, but now only
--functions=<value> is allowed (as well as --functions). The old
behaviour will result in the value being treated as a positional
argument.
The previous testing for --functions=short has been pulled out into a
new test that also tests the other accepted values and option formats.
Reviewed by: ruiu
Differential Revision: https://reviews.llvm.org/D57049
llvm-svn: 351968
Summary:
`CodeViewDebug::lowerTypeMemberFunction` used to default to a `Void`
return type if the function's type array was empty. After D54667, it
started blindly indexing the 0th item for the return type, which fails
in `getOperand` for empty arrays if assertions are enabled.
This patch restores the `Void` return type for empty type arrays, and
adds a test generated by Rust in line-only debuginfo mode.
Reviewers: zturner, rnk
Reviewed By: rnk
Subscribers: hiraditya, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D57070
llvm-svn: 351910
Summary: Enable full support for the debug info.
Reviewers: echristo
Subscribers: jholewinski, aprantl, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D46189
llvm-svn: 351846
Summary: Initial function labels must follow the debug location for the correct relocation info generation.
Reviewers: tra, jlebar, echristo
Subscribers: jholewinski, llvm-commits
Differential Revision: https://reviews.llvm.org/D45784
llvm-svn: 351843
Currently we do not always collapse subsequent .loc 0 0 directives. The
reason is that we were checking for a PrevInstLoc which is not set when
we emit a line-0 record. We should only check the LastAsmLine, which
seems to be created exactly for this purpose.
// When we emit a line-0 record, we don't update PrevInstLoc; so look at
// the last line number actually emitted, to see if it was line 0.
unsigned LastAsmLine =
Asm->OutStreamer->getContext().getCurrentDwarfLoc().getLine();
Differential revision: https://reviews.llvm.org/D56767
llvm-svn: 351395
dbg.value intrinsics can appear in blocks where their operand is not used,
meaning the operand never receives an SDNode, and thus no DBG_VALUE will
be created. Get around this by looking to see whether the operand has already
been allocated a virtual register. This allows dbg.values of Phi node and
Values that are used across basic blocks to successfully be translated into
DBG_VALUEs.
Differential Revision: https://reviews.llvm.org/D56678
llvm-svn: 351358
Eugene Leviant